Magnetic circular dichroism (MCD) has become an improtant and powerful spectroscopic technique for the elucidation of the molecular and electronic structures of complex molecules as a result of advances in theory and in the development of sensitive MCD instruments and superconducting magnets which have been made during the last decade. At the same time, the high cost of adequate instrumentation facilities; the evident need for continuing application (and thef, primarily to inorganic spectroscopy) have caused the biomedical researcher to exclude this technique from his experimental armamentarium. We believe that the biomedical scientist cannot afford this luxury. In support of this assertion, we demonstrate that MCD has important and widespread applications for a broad segment of the biomedical community by describing in detail how MCD is being applied by our group to important problems in clinical medicine as well as in nucleic acid protein research. Major emphasis will be placed in our laboratory on extending our theoretical and empirical knowledge of the MCD behavior of a variety of organic and biochemically important classes of compounds.